Last year certainly wasn't as good of a year for female fronted metal as it was in 2007 IMO, but there were still a number of good releases (Sister Sin, Holy Moses, Katra, Coranatus, Lana Lane, Hydrogyn, Benedictum ... hmm now that I think about it, it was a pretty good year) and this year has already seen a number of releases by great bands with female vocals (Luna Mortis, Doro, Sirenia, Crucified Barbara, A.D.D.) and there are still more on the way (Solna, Autumn, Lacuna Coil, Lunatica, Brave, and Delain just to name a few).

Maybe none of these bands struck a chord with you, but if you haven't heard them yet, you should really give them a chance.
Personally, I'd love to see Hydrogyn, Stolen Babies, Luna Mortis, Sister Sin, A.D.D., Triosphere or Girlschool on the bill. Any of those bands would be great really!